Citing the structure of the cruise industry, with companies technically headquartered outside the U.S., the prevalence of foreign “flagged” ships, and immunity from having to pay U.S. corporate income tax, all while enjoying U.S. support in rescue operations, Rockefeller stated in each letter:

“The advantages this structure presents American consumers and taxpayers are not as clear,” writes the Senator. “The recent cruise vessel mishaps underscore the importance of ensuring that the rules governing cruise industry operations appropriately address the safety, security, and health risks and costs posed by cruise line activities in the country. Toward that end, I ask that you respond to the questions below concerning issues raised by recent events and that follow up on past Committee inquiries to industry representatives.”

In the May 7 letter to Arison, Rockefeller asks whether Carnival will reimburse government rescue costs on an ongoing basis “as a matter of policy going forward.”

Rockefeller also asked Carnival to provide details about its safety, security, and health practices, including its internal fleetwide review that culminated in a program to take steps such as installing redundant emergency power capabilities across the fleet.

Rockefeller noted that “just last month, the toilet system on the Crown Princess reportedly broke down while the vessel was at sea, causing flooding and foul odors in hundreds of rooms over several days and ultimately requiring a return to port.”

The letters to Richard Fain, CEO of Royal Caribbean, and Kevin Sheehan, CEO of Norwegian Cruise Line, take a similar tack.

Rockefeller has been putting intense pressure on the cruise lines, and it’s unclear whether he will push for new hearings and/or legislation. Meanwhile, Senator Charles Schumer has been advocating a cruise passenger bill of rights.

Of the letters, he says, the responses from the CEOs would “help Congress make sure the rules governing the cruise industry provide passengers with the safe and comfortable traveling experiences they expect and deserve, instead of giving the companies a free pass at taxpayer expense.”